Communication system for supporting carrier aggregation and method and apparatus for updating system information thereof

ABSTRACT

A communication system for supporting carrier aggregation and a method and apparatus for updating system information thereof are disclosed. A method for providing system information in the communication system supporting carrier aggregation includes: when system information of said communication system changes, generating first information including information for indicating the change of system information; determining a first cell of a terminal related to the change of system information, wherein said first cell is one of cells to which said terminal connects, and corresponds to a carrier unit currently used by said terminal for keeping connection with a base station of said communication system; and transmitting said first information to said terminal through said first cell.

FIELD

The disclosure relates to the field of carrier aggregation supportingcommunications, and particularly, to a communication system supportingcarrier aggregation and methods and apparatuses for updating the systeminformation thereof. More particularly, the disclosure relates tomethods and apparatuses for providing and receiving system informationin a communication to system supporting carrier aggregation andcommunication system including such apparatuses.

BACKGROUND

Future LTE-A (Long Term Evolution-Advanced) system can support atransmission bandwidth up to 100 MHz, while in LTE standard the largestsupportable transmission bandwidth is 20 MHz. Therefore, it is desiredto aggregate multiple component carriers to meet the higher requirementsfor transmission bandwidth in LTE-A system. Carrier aggregation is atechnique proposed by 3GPP in which multiple component carriers areaggregated for transmission, in order to support the higher requirementsfor transmission bandwidth in future mobile communication system. Theintroduction of carrier aggregation brings about a new opportunity andchallenge in the development of communication technology.

SUMMARY

The following presents a simplified summary of the disclosure in orderto provide a basic understanding of some aspects of the disclosure. Thissummary is not an exhaustive overview of the disclosure. It is notintended to identify key or critical elements of the disclosure or todelineate the scope of the disclosure. Its sole purpose is to presentsome concepts in a simplified form as a prelude to the more detaileddescription that is discussed later.

According to an aspect of the disclosure, a method of providing systeminformation in a communication system supporting carrier aggregation isprovided, which includes: generating, when there is a change in systeminformation of the communication system, first information whichincludes information indicating the change in system information;determining a first cell of a user equipment involved in the change insystem information, wherein the first cell is one of cells to which theuser equipment is connected and corresponds to a component carrier whichis being used by the user equipment and is kept in connection with abase station of the communication system; and transmitting the firstinformation to the user equipment via the first cell.

According to another aspect of the disclosure, an apparatus of providingsystem information in a communication system supporting carrieraggregation is provided, which includes: an information generatingdevice, configured to generate, when there is a change in systeminformation of the communication system, first information whichincludes information indicating that there is a change in systeminformation; a cell determining device, configured to determine a firstcell of a user equipment involved in the change in system information,wherein the first cell is one of cells to which the user equipment isconnected and corresponds to a component carrier which is being used bythe user equipment and is kept in connection with a base station of thecommunication system; and a transmitting device, configured to transmitthe first information to the user equipment via the first cell.

According to another aspect of the disclosure, a method of receivingsystem information in a communication system supporting carrieraggregation is provided, which includes: receiving first informationwhich includes information indicating that there is a change in systeminformation of the communication system via a first cell correspondingto a component carrier which is being used by a user equipment of thecommunication system and is kept in connection with a base station ofthe communication system; and parsing the first information, to obtainthe information indicating that there is the change in systeminformation.

According to another aspect of the disclosure, an apparatus of receivingsystem information in a communication system supporting carrieraggregation is provided, which includes: a receiving device, configuredto receive first information which includes information indicating thatthere is a change in system information of the communication system viaa first cell corresponding to a component carrier which is being used bythe apparatus and is kept in connection with a base station of thecommunication system; and a control device, configured to parse thefirst information, to obtain the information indicating that there isthe change in system information.

According to another aspect of the disclosure, a method of providing andreceiving system information in a communication system supportingcarrier aggregation is provided, which includes: generating, when thereis a change in system information of the communication system, firstinformation which includes information indicating that there is thechange in system information; determining a first cell of a userequipment involved in the change in system information, wherein thefirst cell is one of cells to which the user equipment is connected andcorresponds to a component carrier which is being used by the userequipment and is kept in connection with a base station of thecommunication system; transmitting the first information to the userequipment via the first cell; receiving by the user equipment the firstinformation via the first cell; and parsing by the user equipment thefirst information, to obtain the information indicating that there isthe change in system information.

According to another aspect of the disclosure, a communication system isprovided, which supports carrier aggregation and includes a firstapparatus of providing system information and a second apparatus ofreceiving the system information. The first apparatus includes: aninformation generating device, configured to generate, when there is achange in system information of the communication system, firstinformation which comprises information indicating that there is achange in system information; a cell determining device, configured todetermine a first cell of a user equipment involved in the change insystem information, wherein the first cell is one of cells to which theuser equipment is connected and corresponds to a component carrier whichis being used by the user equipment and is kept in connection with abase station of the communication system; and a transmitting device,configured to transmit the first information to the user equipment viathe first cell. The second apparatus includes: a receiving device,configured to receive first information which includes informationindicating that there is a change in system information of thecommunication system via a first cell corresponding to a componentcarrier which is being used by the apparatus and is kept in connectionwith a base station of the communication system; and a control device,configured to parse the first information, to obtain the informationindicating that there is a change in system information.

In addition, an embodiment of the invention provides computer programfor realizing the above method.

Furthermore, an embodiment of the disclosure provides a computer programproduct in the form of computer readable medium on which there arerecorded computer program codes for the above method.

BRIEF DESCRIPTION OF DRAWINGS

The above and other objects, features and advantages of the embodimentsof the disclosure can be better understood with reference to thedescription given below in conjunction with the accompanying drawings,throughout which identical or like components are denoted by identicalor like reference signs. In addition the components shown in thedrawings are merely to illustrate the principle of the disclosure. Inthe drawings:

FIG. 1 is a schematic diagram illustrating the structure of acommunication system supporting carrier aggregation;

FIG. 2 is a schematic flow chart illustrating a method of updatingsystem information by providing information to a user equipment underthe carrier aggregation (CA) supporting scenario according to anembodiment of the disclosure;

FIG. 3 is a schematic diagram illustrating special cells of some userequipment in the communication system shown in FIG. 1;

FIG. 4 and FIG. 5 are schematic flow charts illustrating the processesof transmitting first information to a user equipment via a first cell,respectively;

FIG. 6 shows an example of a method of updating system information byreceiving information by a user equipment in the carrier aggregationsupporting (CA-S) communication system according to the embodiment shownin FIG. 2;

FIG. 7 shows an example of a receiving process corresponding thetransmitting process as shown in FIG. 4;

FIG. 8 shows an example of a receiving process corresponding thetransmitting process as shown in FIG. 5;

FIG. 9 is a schematic flow chart illustrating a method of notifyingupdate of system information in a CA-S communication system according toan embodiment of the disclosure;

FIG. 10 is a schematic flow chart illustrating a method of receiving thenotification indicating that system information changes in a CA-Scommunication system according to an embodiment of the disclosure;

FIG. 11 and FIG. 12 are schematic flow charts illustrating examples oftransmitting notification information to a UE via the first cell,respectively;

FIG. 13 shows an example of a receiving process corresponding thetransmitting process as shown in FIG. 11;

FIG. 14 shows an example of a receiving process corresponding thetransmitting process as shown in FIG. 12;

FIG. 15 is a schematic flow chart illustrating a method of providingupdated system information in a CA-S communication system according toan embodiment of the disclosure;

FIG. 16 is a schematic flow chart illustrating a method of receivingupdated system information in a CA-S communication system according toan embodiment of the disclosure;

FIG. 17 is a schematic flow chart illustrating a method of receivingupdated system information according to another embodiment of thedisclosure;

FIG. 18 is a schematic flow chart illustrating a method of receivingupdated system information according to yet another embodiment of thedisclosure;

FIG. 19 is a schematic diagram illustrating the process of notifying thechange in system information by using extended conventional signalingunder a CA supporting scenario;

FIG. 20 is a schematic diagram illustrating the process of notifying thechange in system information by using a dedicated signaling under a CAsupporting scenario;

FIG. 21 is a schematic flow chart illustrating a method of providingupdated system information in a CA-S communication system according toan embodiment of the disclosure;

FIG. 22 and FIG. 23 are schematic flow charts illustrating examples oftransmitting first information containing updated system information viathe first cell to a user equipment, respectively;

FIG. 24 to FIG. 26 are schematic flow charts illustrating examples ofreceiving updated system information by a user equipment according toembodiments of the disclosure, respectively;

FIG. 27 is a schematic flow chart illustrating a method of providingsystem information when a component carrier is to be added according toan embodiment of the disclosure;

FIG. 28 is a schematic flow chart illustrating a method of receivingsystem information by a user equipment corresponding to the providingmethod shown in FIG. 27;

FIG. 29 is a schematic flow chart illustrating a method of providingsystem information related to a carrier segment when the carrier segmentis to be added for a currently used component carrier according toanother embodiment of the disclosure;

FIG. 30 is a schematic flow chart illustrating a method of receivingsystem information related to a carrier segment when the carrier segmentis to be added for a currently used component carrier, corresponding tothe providing method shown in FIG. 29;

FIG. 31 is a schematic block diagram illustrating an apparatus ofproviding system information in a CA-S communication system according toan embodiment of the disclosure;

FIG. 32 is a schematic block diagram illustrating an apparatus ofreceiving system information in a CA-S communication system according toan embodiment of the disclosure;

FIG. 33 is a schematic block diagram illustrating an apparatus ofnotifying update of system information in a CA-S communication systemaccording to an embodiment of the disclosure;

FIG. 34 is a schematic block diagram illustrating an apparatus ofreceiving the notification of system information update in a CA-Scommunication system according to an embodiment of the disclosure;

FIG. 35 is a schematic block diagram illustrating an apparatus ofproviding system information when a component carrier is to be addedaccording to an embodiment of the disclosure;

FIG. 36 is a schematic block diagram illustrating an apparatus ofreceiving system information when a component carrier is to be addedaccording to an embodiment of the disclosure;

FIG. 37 is a schematic diagram illustrating a user equipment obtainingupdated system information when a component carrier is to be added undera CA supporting scenario; and

FIG. 38 is a schematic block diagram illustrating the structure of acomputer for realizing embodiment or example of the disclosure.

DETAILED DESCRIPTION

Some embodiments of the present disclosure will be described inconjunction with the accompanying drawings hereinafter. It should benoted that the elements and/or features shown in a drawing or disclosedin an embodiments may be combined with the elements and/or featuresshown in one or more other drawing or embodiments. It should be furthernoted that some details regarding some components and/or processesirrelevant to the disclosure or well known in the art are omitted forthe sake of clarity and conciseness.

Some embodiments of the disclosure provide methods and apparatus ofupdating system information in a CA-S communication system as well as acommunication system including the above apparatus.

FIG. 1 shows an example of a CA-S communication system. As shown in FIG.1, the communication system includes a base station (e.g. e-NodeB) 101and user equipments 102, 103, and 104. In the example of FIG. 1, thecomponent carriers supported by the communication system include CC1,CC2 and CC3. The user equipment 102 can use the component carriers CC1and CC2, the user equipment 103 supports the component carriers CC2 andCC3, and the user equipment 104 supports the component carriers CC1, CC2and CC3. That is, the user equipments 102, 103 and 104 each are acarrier aggregation supporting (CA-S) user equipment. As an example, thecommunication system may further include a carrier aggregationnon-supporting (CA-NS) user equipment 105. As shown in FIG. 1, the userequipment 105 can use only a component carrier, i.e. CC1. Among thecomponent carriers supported by the communication system, the componentcarrier CC1 is contiguous with the component carrier CC2, while thecomponent carrier CC3 is not contiguous with the component carriers CC1and CC2. The communication system as shown in FIG. 1 not only includesCA-S user equipments, but also includes CA-NS user equipments. It shouldbe noted that this is merely an example and the disclosure should not belimited to such communication system. For example, the disclosure may beapplied to a communication system including only a base station and aCA-S user equipment; a communication system including a base station, arelay station and a user equipment or other CA-S communication system,the description of which is not detailed herein.

It should be noted that the so called “User Equipment (UE)” or“Equipment” in the disclosure may include but not limited to a mobiledevice used by a user to access a communication network, such as amobile phone (e.g. 102 and 103 shown in FIG. 1), a personal digitalassistance or a portable personal computer, or the like.

The system information of a communication system needs to be kept newestat all times. When the system information changes, the main node (e.g.the base station) of the communication system needs to notify the userequipments in some way. In a CA-S communication system, a user equipmentmay communicate with the main node of the communication system viamultiple of component carriers. For example, the equipment 104 shown inFIG. 1 may communicate with the base station via 3 component carriersCC1, CC2, and CC3. Different components may have different coverage dueto their different propagation characteristics. When a user equipmentmoves out of the coverage of a component carrier it supported and justat this time the system information needs to be updated, if the updatedinformation is transmitted to this user equipment via the cellcorresponding to this component carrier, the user equipment can notreceive the information. Thus, when the user equipment moves back to thecoverage of this component carrier, this component carrier will beunusable due to the incorrect system information.

FIG. 2 shows a flow chart of a method of updating system information byproviding information to a user equipment under the CA scenarioaccording to an embodiment of the disclosure.

As shown in FIG. 2, the method includes steps S202, S204 and S206.

In step S202, when the system information of the communication systemchanges, the information for indicating the change of the systeminformation is generated. In the following the information generated inthis step is referred to as the first information for conciseness.

The communication system herein is a CA-S communication system, such asthe communication system shown in FIG. 1. Whether the system informationof the communication system changes or not may be judged by the mainnode (For example, the base station) in the communication system. Forexample, related information may be obtained from the correspondingconfiguration file of the main node (the base station), to determinewhether the system information changes.

In step S204, the cell to be used for transmitting the first informationto a user equipment involved in the change of the system information isdetermined.

As described above, in a CA-S communication system, a user equipment maycommunicate with the main node via a plurality of component carriers.Each of the component carriers correspond to a cell. Among the cells towhich each user equipment is connected, there exists a special cellwhich may be used to provide security input and non access stratum (NAS)mobility information, etc. The special cell corresponds to a componentcarrier which is being used by the user equipment for keeping connectionwith the main node (e.g. the base station) in the communication system.As an example, only one special cell can be configured for each userequipment. In other words, the following definition may be made: eachuser equipment is connected to one special cell which corresponds to acomponent carrier keeping connection with the base station, while othercomponent carriers supported by this user equipment can be used as theuplink and/or downlink resources of this user equipment. In an example,the cells corresponding to these other component carriers are alsocalled as serving cells.

FIG. 3 shows the special cells of some user equipments in thecommunication system shown in FIG. 1. As shown in FIG. 3, the userequipment 102 (UE 102) supports component carriers CC1 and CC2, whereinthe cell corresponding to CC1 is the special cell of the user equipment102. The user equipment 103 (UE 103) supports component carriers CC2 andCC3, wherein the cell corresponding to CC2 is the special cell of theuser equipment 103. The user equipment 104 (UE 104) supports componentcarriers CC1, CC2 and CC3, wherein the cell corresponding to CC3 is thespecial cell of the user equipment 104.

When there is a change in the system information, the base station mayjudge to which user equipment(s) (i.e. the user equipment(s) affected bythe change) the change should be notified based on correspondingconfiguration files, determines the special cell of each of the userequipment(s) as the cell for transmitting the first information to theeach of the user equipment(s).

As an example, the base station may select, among one or more cells towhich a user equipment is connected, one cell as the special cell ofthis user equipment. Particularly, the base station may select thespecial cell of a user equipment according to the correspondingconfiguration file or according to the information fed back by the userequipment (e.g. the channel quality, the signal strength, and thelocation of the user equipment, etc), based on a criterion (e.g. thisspecial cell always keeps connection to the base station). For example,before transmitting the first information to a user equipment, the basestation may select the special cell of a user equipment and notify theresult of selection to the user equipment. For another example, the basestation may perform the selecting step at a regular interval or asrequired, for example, when the user equipment moves to the edge of thecoverage of a cell or moves out of the coverage of a cell, and maynotify the result of selection to the user equipment and stores theresult of the corresponding configuration file of the base station. Inthis way, when the base station needs to determine the special cell ofthe user equipment, it may query the corresponding configuration file.

As another example, the special cell may be selected by the userequipment and then notified to the base station. For example, the userequipment may determine the connection states of the cells supported bythe user equipment based on its own configuration and select, among thecells that are kept in connection with the base station, one cell as thespecial cell for transmitting system information. For example, the userequipment may reconfigure or select its special cell at a regularinterval, or based on its mobility conditions (e.g. when it moves to theedge, or moves out, of a cell) or other information (e.g. the channelquality, the signal strength, etc) and transmit the information of thespecial cell to the base station. The base station may stores theinformation in corresponding configuration file. Thus, when the basestation needs to determine the special cell of the user equipment, itmay query the corresponding configuration file. Alternatively, when thebase station needs to determine the special cell of the user equipment,the base station may transmit to the user equipment a requestinstructing the user equipment to feed back the information of thespecial cell of the user equipment.

As described above, the special cell determined in step S204 is one ofthe cells to which the user equipment is connected, and corresponds to acomponent carrier which is being used by the user equipment and is keptin connection with the main node of the communication system. In thefollowing, the special cell is also called as the first cell.

Then in step S206, the first information is sent to the user equipmentvia the first cell.

In the CA-S communication system, the first cell is always kept inconnection with the main node (e.g. the base station). Thus, by usingthe above method, the case that the user equipment can not receive theupdated system information can be avoided, so that the systeminformation can be updated or provided in time. In addition, the basestation needs not to transmit the system information or notify theupdate of the system information via each of the cells supported by theuser equipment, thereby decreasing the signaling load of the wholesystem.

FIG. 4 and FIG. 5 each show an example of the process of transmittingthe first information to the user equipment via the first cell.

In the example of FIG. 4, the process of transmitting the firstinformation to the user equipment via the first cell may includesub-steps S406-1 and S406-2. In sub-step S406-1, the first informationgenerated in the preceding step is encapsulated in a dedicated signaling(also referred to as the first dedicated signaling). Then in sub-stepS406-2, the first dedicated signaling is sent to the user equipment viathe first cell. In this example, the signaling generated in sub-stepS406-1 is a dedicated signaling, thus in sub-step S406-2 this dedicatedsignaling is transmitted via the dedicated channel of the first cell.

In the disclosure, transmitting a dedicated signaling via a cellcorresponding to a component carrier means that the dedicated signalingis transmitted via the dedicated channel of the cell, the description ofwhich is not repeated hereinafter. The dedicated channel may be aDedicated Control Channel (DCCH), such as the DCCH defined in LTEstandard (e.g. ETSI TS 136 331 V8.5.0).

When a communication system includes many CA-S user equipments and thenumber of configured component carriers is relatively large, usingdedicated signaling to transmit the first information to the userequipments (i.e. transmitting the first information via the dedicatedchannels of the first cells) will increase the signaling load of thesystem significantly. In such a case, the example of FIG. 5 may be used.As shown in FIG. 5, the process of transmitting the first information tothe user equipment via the first cell may include sub-steps S506-1 andS506-2. In sub-step S506-1, the first information generated in thepreceding step is encapsulated in a broadcast signaling (also called asthe first broadcast signaling). Then in sub-step S506-2, the firstbroadcast signaling is sent to user equipment via the broadcast channelof the first cell. The broadcast channel may be a Broadcast ControlChannel (BCCH), such as the BCCH defined in LTE standard (e.g. ETSI TS136 331 V8.5.0). Compared with the dedicated signaling in the example ofFIG. 4, using the broadcast signaling of FIG. 5 can decrease thesignaling load of the system effectively.

The embodiment and examples shown in FIG. 2, FIG. 4 and FIG. 5illustrate examples of the processes of transmitting information from amain node (e.g. the base station) of the communication system to a userequipment. FIG. 6 to FIG. 8 respectively show the corresponding processof receiving the information by a user equipment.

Particularly, FIG. 6 shows an example of a method of receivinginformation by a user equipment so as to update the system informationin the CA-S communication system according to the embodiment of FIG. 2.

As shown in FIG. 6, the method may include steps S607 and S609.

In step S607, the user equipment receives the first informationtransmitted by the base station via the first cell, the firstinformation includes information indicating that the system informationchanges. In other words, the user equipment receives the firstinformation by listening to the component carrier (also called as thefirst component carrier) corresponding to the first cell. The first cellhas been described above, the description of which is not repeated.

In step S609, the user equipment parses the received first informationto obtain the information indicating that the system informationchanges, so as to perform the update of the system information.

By using the above receiving method, the user equipment may get known ofthe change of the system information in time. Since the user equipmentkeeps being connected with the base station via the first cell (i.e. thespecial cell), the case that the user equipment can not receive theupdated system information can be avoided. In addition, by using thefirst cell, the user equipment needs not to listen to all the cellscorresponding to its supportable component carriers, thereby reducingthe power consumption of the user equipment significantly andlengthening the lift time of the battery of the user equipment.

The transmitting process shown in FIG. 2 and the receiving process shownin FIG. 6 constitute an example of updating system information in theCA-S communication system.

FIG. 7 shows an example of receiving process corresponding to thetransmitting process shown in FIG. 4. As shown in FIG. 4, the firstinformation is encapsulated in a dedicated signaling (i.e. the firstdedicated signaling) and is sent to the user equipment via the dedicatedchannel of the first cell. Thus in step S707, the user equipmentreceives the first dedicated signaling which contains the firstinformation via the first cell thereof. In other words, the userequipment listens to the dedicated channel of its first cell to receivethe first dedicated signaling. Similar to step S609, in step S709, theuser equipment parses the first dedicated signaling, to obtain theinformation indicating that the system information changes.

FIG. 8 shows an example of receiving process corresponding to thetransmitting process shown in FIG. 5. As shown in FIG. 5, the firstinformation is encapsulated in the broadcast signaling (i.e. the firstbroadcast signaling) and is sent to the user equipment via the broadcastchannel of the first cell. Thus in step S807, the user equipmentreceives the first broadcast signaling containing the first informationvia the broadcast channel of the first cell. In other words, the userequipment listens to the broadcast channel of the first cell to receivethe first broadcast signaling. Step S809 is similar to step S609 orS709, the description of which is not repeated here.

The transmitting process shown in FIG. 4 and the receiving process shownin FIG. 7, the transmitting process shown in FIG. 5 and the receivingprocess shown in FIG. 8 respectively constitute examples of updating thesystem information. Compared with the method of using dedicatedsignaling as shown in FIG. 4 or FIG. 7, the examples shown in FIG. 5 andFIG. 8 utilize the broadcast signaling, by which the signaling load ofthe system may be decreased.

In addition, by using the first cell (the dedicated channel or thebroadcast channel thereof), the user equipment needs not to listen toall the cells corresponding to all its supportable component carriers,thereby reducing the power consumption of the user equipmentsignificantly and lengthening the lift time of the battery of the userequipment.

As an embodiment, the first information may contain only the informationindicating that the system information changes, and in this case, thebase station at the network side will transmit the updated systeminformation by subsequent transmitting processes and the user equipmentmay receive the updated system information by subsequent receivingprocesses, which will be described below.

As another embodiment, the first information may further include theupdated system information. That is, at the network side the basestation transmit the updated system information to the user equipmentdirectly via the first cell; and the user equipment may obtain theupdated system information by parsing the first information, which willbe described below.

As an example, the first information may further include the information(also referred to as the third-information) indicating whether thechange of the system information affects the CA transmission. Forexample, the third information may indicate the system information ofwhich part of the system changes and the user equipment may determinewhether the change affects the CA transmission based on thisinformation.

FIG. 9 shows an example of a method of notifying the update of systeminformation in a CA-S communication system according to an embodiment ofthe disclosure. In the method, the network side of the communicationsystem (e.g. the base station) notifies the user equipment of the changeof the system information via the first cell. The first cell herein isthe same as described above.

As shown in FIG. 9, the method includes steps S902, S904 and S906.

In step S906, when the system information of the communication systemchanges, the notification information indicating that the systeminformation changes is generated. The notification information mayinclude only the information indicating that the system informationchanges. As described above, the notification information may beregarded as an example of the first information.

Similar to the above embodiments, the communication system herein is aCA-S communication system, such as the communication system shown inFIG. 1. Whether the system information of the communication systemchanges or not may be judged by the main node (e.g. the base station) inthe communication system. For example, related information may beobtained from the corresponding configuration file of the main node (thebase station), to determine whether the system information changes.

In step S904, the cell to be used for transmitting the notificationinformation to a user equipment which is involved in the change of thesystem information is determined.

Particularly, the base station may judge to which user equipment(s)(i.e. the user equipment(s) involved in the change) the change should benotified based on corresponding configuration files, determines thespecial cell of each of the user equipment(s) as the cell fortransmitting the first information to the each of the user equipment(s).The special cell of a user equipment may be determined by using theabove described method, the description of which is not repeated here

Similar to the above embodiments, the cell determined in step 904 is oneof the cells to which the user equipment is connected and corresponds tothe component carrier which is being used by the user equipment andkeeps in connection with the main node of the communication system. Thiscell is also called as the first cell or the special cell.

Then in step S906, the notification information is sent to the userequipment via the first cell.

Since the first cell always keeps in connection with the base station,the case that the user equipment can not receive the notificationinformation can be avoided by using the above method. In this way thechange of the system information can be notified to the user equipmentin time. In addition, the base station needs not to send thenotification information to the user equipment via each of a pluralityof cells, by which the signaling load of the system may be reduced.

FIG. 10 shows an example of a method of receiving notification that thesystem information changes in a CA-S communication system according toan embodiment of the disclosure. In the method, the user equipment ofthe communication system receives the notification informationindicating that the system information changes from the base station bylistening to the first cell. The first cell herein is the same asdescribed above.

As shown in FIG. 10, the method includes steps S1007 and S1009.

In step S1007, the user equipment receives the notification informationindicating that the system information changes which is transmitted fromthe base station via the first cell. In other words, the user equipmentlistens to the component carrier (also called as the first componentcarrier) corresponding to the first cell to receive the notificationinformation.

In step S1009, the user equipment parses the received notificationinformation, so as to get aware that the system information changes.

By using the above method, the user equipment can know the change of thesystem information in time, so as to update the system informationsubsequently. Since the user equipment keeps in connection with the basestation via the first cell (i.e. the special cell), the case that it cannot get the notification of the change can be avoided. In addition, byusing the first cell, the user equipment needs not to listen to all thecells corresponding to its supportable component carriers, by which thepower consumption of the user equipment can be reduced significantly andthe lift time of the battery of the user equipment can be lengthened.

The transmitting process shown in FIG. 9 and the receiving process shownin FIG. 10 constitute an example of updating the system information inthe CA-S communication system.

FIG. 11 and FIG. 12 respectively show examples of transmittingnotification information to the user equipment via the first cell.

In the example of FIG. 11, the step of transmitting the notificationinformation via the first cell to the user equipment may includesub-steps S1106-1 and S1106-2. In sub-step S1106-1, the notificationinformation generated in the preceding step is encapsulated in adedicated signaling (also called as the first dedicated signaling). Thenin sub-step S1106-2, the first dedicated signaling is sent to the userequipment via the first cell. The signaling generated in sub-stepS1106-1 is a dedicated signaling, and in sub-step S1106-2 the dedicatedsignaling is sent via the dedicated channel of the first cell.

When a communication system includes many CA-S user equipments and thenumber of configured component carriers is relatively large, usingdedicated signaling to transmit the first information to the userequipments (i.e. transmitting the first information via the dedicatedchannels of the first cells) will increase the signaling load of thesystem significantly. In such a case, the example of FIG. 12 may beused. As shown in FIG. 12, the process of transmitting the notificationinformation to the user equipment via the first cell may includesub-steps S1206-1 and S1206-2. In sub-step S1206-1, the notificationinformation generated in the preceding step is encapsulated in abroadcast signaling (also called as the first broadcast signaling). Thenin sub-step S1206-2, the first broadcast signaling is sent to userequipment via the broadcast channel of the first cell. Compared with thededicated signaling in the example of FIG. 11, using the broadcastsignaling of FIG. 12 can decrease the signaling load of the systemeffectively.

FIG. 13 shows an example of a receiving process corresponding to thetransmitting process shown in FIG. 11. As shown in FIG. 11, the firstinformation is encapsulated in a dedicated signaling (the firstdedicated signaling) and is sent to the user equipment via the firstcell. Thus in step S1307, the user equipment receives the firstdedicated signaling containing the notification information via thecomponent carrier (also called as the first component carrier)corresponding to its first cell. In other words, the user equipmentlistens to the dedicated channel of the first cell to receive the firstdedicated signaling. Similar to step S1009, in step S1309 the userequipment parses the first dedicated signaling to obtain thenotification information indicating that the system information changes,so as to get aware of the change of the system information.

FIG. 14 shows an example of receiving process corresponding to thetransmitting process shown in FIG. 12. As shown in FIG. 12, thenotification information is encapsulated in the broadcast signaling (thefirst broadcast signaling) and is sent to the user equipment via thebroadcast channel of the first cell. Thus in step S1407, the userequipment receives the first broadcast signaling containing thenotification information via the broadcast channel of the first cell. Inother words, the user equipment listens to the broadcast channel of thefirst cell to receive the first broadcast signaling. Step S1409 issimilar to step S1009 or S1309, the description of which is not repeatedhere.

The transmitting process shown in FIG. 11 and the receiving processshown in FIG. 13, the transmitting process shown in FIG. 12 and thereceiving process shown in FIG. 14 respectively constitute examples ofupdating the system information. Compared with the method of usingdedicated signaling as shown in FIG. 11 or FIG. 13, the examples shownin FIG. 12 and FIG. 14 utilize the broadcast signaling, by which thesignaling load of the system may be decreased.

In addition, by using the first cell (the dedicated channel or thebroadcast channel), the user equipment needs not to listen to all thecells corresponding to its supportable component carriers, by which thepower consumption of the user equipment can be reduced and the life timeof the battery of the user equipment can be lengthened.

It should be noted, the dedicated signaling and the broadcast signalingin this disclosure each may be a newly defined signaling, or may be asignaling obtained by extending a known signaling. The disclosure is notlimited to any of the examples.

FIG. 15 shows a method of providing the updated system information inthe CA-S communication system according to an embodiment of thedisclosure. The method shown in FIG. 15 is based on the example shown inFIG. 9, or FIG. 11, or FIG. 12. The difference lies in that, the methodof FIG. 15 further includes a process of transmitting the updated systeminformation.

As shown in FIG. 15, the method includes steps S1502, S1504, S1506,S1512 and S1514.

Steps S1502, S1504 and S1506 may be similar to the corresponding stepsshown in FIG. 9, FIG. 11 or FIG. 12, the description of which is notrepeated here.

In step S1512, the network side (e.g. the base station) of thecommunication system encapsulated the updated system information in abroadcast signaling (also called as the second broadcast signaling).Then in step S1514, the second broadcast signaling is transmitted to theuser equipment via the cell (also called as the second cell)corresponding to the component carrier involved in the change of thesystem information.

FIG. 16 shows a method of receiving the updated system information inthe CA-S communication system according to an embodiment of thedisclosure. The method shown in FIG. 16 is based on the method shown inFIG. 10, FIG. 13 or FIG. 14. The difference lies in that, the methodshown in FIG. 16 further includes a process of receiving the updatedsystem information.

As shown in FIG. 16, the method includes steps S1607, S1609 and S1611.

Step S1607 and S1609 are similar to the corresponding steps shown inFIG. 10, FIG. 13 or FIG. 14, the description of which is not repeatedhere.

As shown in FIG. 15, the network side (e.g. the base station) of thecommunication system encapsulated the updated system information in thesecond broadcast signaling and transmits the he second broadcastsignaling via the broadcast channel of the second cell. Accordingly,since the user equipment does not know on which cell's broadcast channelthe base station will transmit the updated system information, thus whenthe user equipment gets aware that the system information changes, itstarts to perform the process shown in step S1611. That is, the userequipment starts listening to the broadcast channels of all the cellscorresponding to its supportable component carriers, in order to receivethe second broadcast signaling. After receiving the second broadcastsignaling, the user equipment parses it to obtain the updated systeminformation.

The transmitting process shown in FIG. 15 and the receiving processshown in FIG. 16 constitute an example of updating the systeminformation in the CA-S communication system.

In the above embodiments, the network side (the base station) of thecommunication sends the updated system information via the second cellcorresponding to an involved component carrier, and the UE needs tolistens to all the cells corresponding to all of its supportablecomponent carriers. With the method, no additional information is neededto be transmitted during the process of providing the notificationinformation (e.g. steps S1502-S1506). Thus the process of notifying thechange of the system information can be simplified.

FIG. 17 shows a method of receiving the updated system information inthe CA-S communication system according to another embodiment of thedisclosure. In the embodiment, the notification information may furtherinclude information (also called as the second information) foridentifying a component carrier involved in the change of the systeminformation. As shown in FIG. 17, after receives the notificationinformation including the second to information and the informationindicating that the system information changes in step S1707, the userequipment parses the notification information to obtain the secondinformation in step S1709. Then in step S1711, the user equipmentlistens to the broadcast channel of the cell corresponding to thecomponent carrier involved in the change of the system information basedon the second information, to obtain the updated system information. Inthe embodiment, the user equipment needs not to listen to the broadcastchannels of all the cells corresponding to all of its supportablecomponent carriers. Compared with the method shown in FIG. 16, with themethod of FIG. 17, the power consumption of the user equipment can bereduced significantly and the life time of the battery of the userequipment can be lengthened.

FIG. 18 shows a method of receiving the updated system informationaccording to another embodiment of the disclosure. In the embodiment,the notification information may further include the information (alsocalled as the third information) indicating whether the change of thesystem information affects the CA transmission. For example, the thirdinformation may indicate that change of the system information occurs inwhich part(s) of the communication system and the user equipment canjudge whether the change affects its CA transmission based on thisinformation. Particularly, when the user equipment receives thenotification information containing the third information and theinformation indicating that the system information changes in stepS1807, it may parses the notification information to obtain the thirdinformation in step 1809. Then in step S1810, the user equipment decideswhether to receive the updated system information based on the thirdinformation. For example, if the user equipment supports CA and thethird information indicates that the change of the system informationdoes not affect the CA transmission, the user equipment may choose notto receive the updated system information. On the other hand, if theuser equipment does not support CA and the third information indicatesthat the change of the system information affects the CA transmission,the user equipment, the user equipment may also choose not to receivethe updated system information. If decides to receive the updated systeminformation, the user equipment listens to the corresponding channel toreceive the updated system information in step S1811. Step S1811 may besimilar to step S1611 or step S1711, the description of which is notrepeated here.

In the transmitting and receiving processes shown in FIG. 15 and FIG.16, the updated system information is encapsulated in the secondbroadcast signaling and is transmitted and received via the broadcastchannel of the second cell. In another embodiment, the updated systeminformation may be encapsulated in a dedicated signaling (also called asthe third dedicated signaling) and is transmitted and received via thededicated channel of the second cell. In this embodiment, thenotification information further contains the information (the secondinformation) for identifying a component carrier involved in the changeof the system information. When the user equipment receives thenotification information including the second information, it parses thenotification information to obtain the second information and based onthe second information, it listens to the dedicated channel of the cellcorresponding to the component carrier involved in the change, so as toobtain the updated system information. In the embodiment, the userequipment needs not to listen to the broadcast channels of all the cellscorresponding to all of its supportable component carriers. Thus, thepower consumption of the user equipment can be reduced significantly andthe life time of the battery of the user equipment can be lengthened.

As described above, the broadcast signaling and the dedicated signalingeach may be a newly defined signaling, or may be an extension to a knownsignaling.

As an example, the first broadcast signaling may be an extension to thePaging message in LTE Release 8, or may be an extension to the systeminformation block (SIB1) message. For example, the second informationand/or the third information can be inserted in the Paging or SIB1message. Particularly, two indicators may be inserted in the Paging orSIB1 message, including a first indicator (e.g.SystemInfoUpdateCCIndicator) and a second indicator (e.g.CriticalSystemInfoIndicator). The first indicator may contain the secondinformation, i.e. to identify the system information of which componentcarrier changes. The second indicator contains the third information,i.e. to identify whether the change of the system information affectsthe CA transmission (e.g. it may indicate which part's systeminformation changes, and the user equipment may determine whether its CAtransmission is affected based on this information). FIG. 19 is aschematic diagram showing the notification of the change of systeminformation by using the Paging or SIB1 message as the first broadcastsignaling under a CA scenario. As shown in FIG. 19, the extended Pagingor SIB1 message is transmitted via the broadcast channel of the firstcell (corresponding to CC1) of the user equipment 102. Then, the updatedsystem information is transmitted via the cell corresponding to CC2. Ofcourse, this is only an example of using the first broadcast signaling,and the disclosure should not be regarded as being limited to this. Asdescribed above, the first broadcast signaling may be a newly definedsignaling.

Similar to the first broadcast signaling, the first dedicated signalingmay be a newly defined signaling, or may be an extension to a knownsignaling. Also similar to the first broadcast signaling, the firstdedicated signaling may contain the second information and/or the thirdinformation. For example, the first dedicated signaling may contain twoindicators, such as the first indicator (e.g.SystemInfoUpdateCCIndicator) and the second indicator (e.g.CriticalSystemInfoIndicator). The first indicator may contain the secondinformation, i.e. to identify the system information of which componentcarrier changes. The second indicator contains the third information,i.e. to identify whether the change of the system information affectsthe CA transmission (e.g. the information may indicate which part'ssystem information changes, and the user equipment may determine whetherits CA transmission is affected based on this information). FIG. 20 is aschematic diagram showing the notification of the change of systeminformation by using the first dedicated signaling under a CA scenario.As shown in FIG. 20, the first dedicated signaling (e.g. theSystemInfoUpdate message as shown) is transmitted via the dedicatedchannel of the first cell (corresponding to CC 1) of the user equipment102. Then, the updated system information is transmitted via the cellcorresponding to CC2.

FIG. 21 shows a method of providing the updated system information inthe CA-S communication system according to an embodiment of thedisclosure. In the method of FIG. 21, the network side (the basestation) of the communication system transmits the updated systeminformation to the user equipment via the first cell (the special cell)of the user equipment.

As shown in FIG. 21, the method includes steps S2102, S2104 and S2106.

In step S2102, when the system information of the communication systemchanges, the first information is generated. Different from theembodiment shown in FIG. 2, in this embodiment the first informationfurther includes the updated system information, in addition to theinformation indicating that the system information changes.

Similar to the above embodiments, whether the system information of thecommunication system changes or not may be judged by the main node (e.g.the base station) of the communication system. For example, relatedinformation may be obtained from the corresponding configuration file ofthe main node (the base station), to determine whether the systeminformation changes. The updated system information may also be obtainedfrom the corresponding configuration file of the base station.

In step S2104, the cell, i.e. the first cell, to be used to transmit thefirst information to the user equipment involved in the change of thesystem information is determined. The first cell here is the same asdescribed above, the description of which is not repeated.

When there is a change in the system information, the base station mayjudge to which user equipment(s) (i.e. the user equipment(s) affected bythe change) the change should be notified based on correspondingconfiguration files, determines the special cell of each of the userequipment(s) as the cell for transmitting the first information to theeach of the user equipment(s). The special cell of a user equipment canbe determined by using the method as described above, the description ofwhich is not repeated here.

Then in step S2106, the first information is sent to the user equipmentvia the first cell.

Since the first cell is always kept in connection with the main node(e.g. the base station). Thus, by using the above method, the case thatthe user equipment can not receive the updated system information can beavoided.

FIG. 22 and FIG. 23 respectively show the processes of transmitting thefirst information containing the updated system information to the userequipment via the first cell.

In the example of FIG. 22, the step of transmitting the firstinformation to the user equipment via the first cell may includesub-steps S2206-1 and S2206-2. In sub-step S2206-1, the firstinformation containing the updated system information generated in stepS2102 is encapsulated in a dedicated signaling (also called as the firstdedicated signaling). Then in sub-step S2206-2, the first dedicatedsignaling is sent to the user equipment via the first cell. That is, thefirst dedicated signaling is sent via the dedicated channel of the firstcell.

In the example of FIG. 23, the step of transmitting the firstinformation to the user equipment via the first cell may includesub-steps S2306-1 and S2306-2. In sub-step S2306-1, the firstinformation containing the updated system information generated in stepS2102 is encapsulated in a broadcast signaling (also called as the firstbroadcast signaling). Then in sub-step S2306-2, the first broadcastsignaling is sent to the user equipment via the broadcast channel of thefirst cell. Compared with the method of using the dedicated signalingshown in FIG. 22, using the broadcast signaling as shown in FIG. 23 caneffectively reduce the signaling load of the system.

FIG. 24 to FIG. 26 show examples of receiving the updated systeminformation by the user equipment.

FIG. 24 shows a method of receiving the updated system information bythe user equipment in the CA-S communication system based on theembodiment of FIG. 21.

As shown in FIG. 24, the method includes steps S2407 and S2409.

In step S2407, the user equipment receives the first information thetransmitted by the base station via the first cell. The firstinformation contains information indicating that the system informationchanges and the updated system information. In other words, the userequipment listens to the component carrier (also called as the firstcomponent carrier) corresponding to the first cell to receive the firstinformation.

In step S2409, the user equipment pareses the first information to getaware of the change of the system information and to obtain the updatedsystem information.

By using the method, the user equipment may get the updated systeminformation in time. Since the user equipment keeps being connected withthe base station via the first cell (i.e. the special cell), the casethat the user equipment can not receive the updated system informationcan be avoided. In addition, by using the first cell, the user equipmentneeds not to listen to all the cells corresponding to its supportablecomponent carriers, thereby reducing the power consumption of the userequipment significantly and lengthening the lift time of the battery ofthe user equipment.

The transmitting process of FIG. 21 and the receiving process of FIG. 24constitute an example of updating the system information in the CA-Scommunication system.

FIG. 25 shows a receiving process corresponding to the transmittingprocess of FIG. 22. As shown in FIG. 22, the first information isencapsulated in a dedicated signaling (the first dedicated signaling)and is sent to the user equipment via the dedicated channel of the firstcell. Thus in step S2507, the user equipment receives the firstdedicated signaling containing the first information via its first cell.In other words, the user equipment listens to the dedicated channel ofthe first cell to receive the first dedicated signaling. Similar to stepS2409, in step S2509 the user equipment pareses the first dedicatedsignaling to obtain the updated system information.

FIG. 26 shows a receiving process corresponding to the transmittingprocess of FIG. 23 As shown in FIG. 23, the first information isencapsulated in a broadcast signaling (the first broadcast signaling)and is sent to the user equipment via the broadcast channel of the firstcell. Thus in step S2607, the user equipment receives the firstbroadcast signaling containing the first information via the broadcastchannel of the first cell. In other words, the user equipment listens tothe broadcast channel of the first cell to receive the first broadcastsignaling. Step S2609 is similar to step S2409 or S2509, the descriptionof which is not repeated here.

The transmitting process of FIG. 22 and the receiving process of FIG.25, the transmitting process of FIG. 23 and the receiving process ofFIG. 26 respectively constitute examples of updating the systeminformation of the disclosure. Compared with the methods of using thededicated signaling in FIG. 22 and FIG. 25, using the broadcastsignaling as shown in FIG. 23 and FIG. 26 can effectively reduce thesignaling load of the system.

In addition, by using the first cell (the dedicated channel or thebroadcast channel), the user equipment needs not to listen to all thecells corresponding to its supportable component carriers, therebyreducing the power consumption of the user equipment significantly andlengthening the lift time of the battery of the user equipment.

In addition, the change of system information described in thedisclosure may include any change in the system information resultedfrom the change of the system configuration and architecture. Forexample, the change may include but not limited to: adding a carriersegment to an activated component carrier, adding an extension carrier,activating (adding) a new component carrier, and the like. Thus, theupdated system information may include any system information related tosuch changes. For example, when adding a carrier segment to an activatedcomponent carrier, the updated system information may includeconfiguration information related to the carrier segment; when adding anextension carrier for a user equipment, the updated system informationmay include configuration information related to the extension carrier;when adding an extension carrier, activating (adding) a new componentcarrier, the updated system information may include configurationinformation related to the new component carrier, the description ofwhich is not detailed herein.

FIG. 27 shows a method of providing the system information in the case acomponent carrier is to be added according to an embodiment of thedisclosure.

As shown in FIG. 27, the method includes steps S2702, S2704, S2706 andS2708.

In step S2702, when a component carrier is to be added, the firstinformation is generated. The first information may include theinformation indicating that a component carrier is to be added and thesystem information related to the component carrier.

In step S2704, the cell (the first cell) to be used to transmit thefirst information to the user equipment for which component carrier isto be added is determined. The first cell herein has been describedabove and will not be repeated here.

Particularly, the base station determines the special cell of the userequipment based on corresponding configuration file, as the cell fortransmitting the first information to the user equipment. The specialcell of the user equipment can be determined by using the methoddescribed above, the description of which is not repeated here.

In step S2706, the first information is encapsulated in a dedicatedsignaling (also called as the second dedicated signaling). Then in stepS2708, the second dedicated signaling is sent to the user equipment viathe first cell. That is, the second dedicated signaling is transmittedvia the dedicated channel of the first cell.

Since the first cell is always kept in connection with the main node(e.g. the base station). Thus, by using the above method, the systeminformation related to the component carrier to be added can be sent tothe user equipment in time. And the case that the user equipment can notreceive the updated system information can be avoided.

FIG. 28 shows an example of receiving the system informationcorresponding to the transmitting process of FIG. 27.

As shown in FIG. 28, the method includes steps S2807, S2809 and S2811.

In step S2807, the user equipment receives the second dedicatedsignaling via the dedicated channel of the first cell.

In step S2809, the user equipment parses the second dedicated signaling,to obtain the component carrier to be added and to obtain the systeminformation related to the component carrier.

In step S2811, the user equipment configures the component carrier to beadded based on the system information so as to activate the componentcarrier.

By using the method, the user equipment may obtain the updated systeminformation in time. Since it keeps in connection with the base stationvia the first cell (the special cell), the case that the systeminformation can not be received is avoided. In addition, by using thededicated signaling, the CA-NS user equipment will not receive suchinformation.

The transmitting process of FIG. 27 and the receiving process of FIG. 28constitute an example of updating the system information in the CA-Scommunication system.

In an example, the component carrier to be added may be an extensioncarrier. And in such a case, step S2706 may include encapsulating theconfiguration information related to the extension carrier in the seconddedicated signaling. Accordingly, after the user equipment receives thesecond dedicated signaling containing the configuration informationrelated to the extension carrier, it parses the second dedicatedsignaling to obtain the configuration information and configures theextension carrier based on configuration information.

In another example, the component carrier to be added may include acarrier segment to be attached to the component carrier. In this case,the network side (the base station) of the communication system maytransmit the configuration information related to carrier segment to theuser equipment via the first cell. As an example, the configurationinformation related to the carrier segment and the system informationrelated to the component carrier to be added both may be encapsulated inthe second dedicated signaling. Accordingly, the user equipment receivesthe system information related to the component carrier via thededicated channel of the first cell and configures the component carrierbased on the information. If the configuration information related tothe carrier segment and the system information related to the componentcarrier to be added both are encapsulated in the second dedicatedsignaling, the user equipment may further obtain the configurationinformation related to the carrier segment by parsing the seconddedicated signaling and configure the carrier segment based on theconfiguration information.

In an example, the system information related to the component carrierto be added may include transmission bandwidth configuration informationand frequency band indicator information related to the componentcarrier to be added. If the component carrier to be added is used foruplink transmission or if the component carrier to be added is used fordownlink transmission but uplink information needs to be configured forit, the system information related to the component carrier to be addedmay further include the uplink carrier frequency, the uplinktransmission bandwidth and the configuration information of uplinkchannels of the component carrier to be added. If the component carrierto be added is for downlink transmission, the system information relatedto the component carrier to be added may further include theconfiguration information of the downlink channels of the componentcarrier to be added.

As an example, the system information may adopt the format of the systeminformation defined in LTE standard. The system information may includemain information block (MIB) and one or more system information block(SIB). The MIB contains some most important information and relatedparameters for obtaining other important information from the cell, suchas the downlink bandwidth configuration, the physical hybrid automaticrepeat request indicator channel configuration, and the like. An SIB mayinclude information such as whether the user equipment is allowed to beconnected to a cell, the radio resource configuration information of theuser equipment, the cell reselection information, and the like.

As described above, the second dedicated signaling may be newly definedsignaling, or may be an extension to a known signaling. As an example,the second dedicated signaling may be an extension to the radio resourcecontrol connection reconfiguration message (e.g.RRCConnectionReconfigurationmessage). In this case, step S2706 mayinclude encapsulating the first information in the radio resourcecontrol connection reconfiguration message. By using the knownsignaling, the trouble of redefining a new message structure is avoided.

As an example, the extension to the radio resource control connectionreconfiguration message (RRCConnectionReconfiguration) may include thesystem information, such as MIB, SIB1, and SIB2, etc. Particularly, MIBmay include the following:

-   -   dl-Bandwidth: transmission bandwidth configuration information,        i.e. the number of RBs in the downlinks.    -   phich-Config: PHICH (Physical hybrid-ARQ indicator channel)        channel configuration information.

SIB1 may include: freqBandIndicator: which is a frequency indicatorflag.

If the component carrier to be added is for uplink transmission or itneeds to configure the uplink information of a downlink componentcarrier, SIB2 may include the following:

-   -   ul-CarrierFreq: carrier frequency.    -   ul-Bandwidth: uplink transmission bandwidth, i.e. the number of        RBs in the uplink.    -   rach-Config: RACH (Random Access Channel) channel configuration        information.    -   prach-Config: PRACH (Physical Random Access Channel) channel        configuration information.    -   pusch-Config: PUSCH (Physical uplink shared channel) channel        configuration information.    -   pucch-Config: PUCCH (Physical uplink control channel) channel        configuration information.    -   soundingRS-UL-Config: SoundingRS uplink configuration        information.    -   uplinkPowerControl: uplink power control.    -   ul-CyclicPrefixLength: uplink cyclic prefix length.

If the component carrier to be added is for downlink transmission, SIB2may include:

-   -   mbsfn-SubframeConfigList: the subframe list reserved for MBSFN        (Multimedia Broadcast multicast service Single Frequency        Network) of downlink.    -   bcch-Config: BCCH channel configuration information.    -   pcch-Config: PCCH (Paging Control Channel) channel configuration        information.    -   pdsch-Config: PDSCH (Physical downlink shared channel) channel        configuration information.

Of course, the above system information is merely an example, and thedisclosure is not limited to this. In addition, when using a dedicatedsignaling, the system information may be transferred in the format of anincrement signaling. For example, the related information of the firstcell may be used as default information, and in this case, the update ofthe related information may be identified with an on flag “ON”. Forexample, when the on flag “ON” is 1, it means that there is update inthe related information; and when the flag “ON” is 0, it means thatthere is no update in the related information. When receiving the systeminformation transmitted via an increment signaling, the user equipmentmay determine which part's the system information is updated.

The second dedicated signaling and the third dedicated signaling bothcan be transmitted in the format of an increment signaling. When thesystem information or the updated system information is sent via adedicated signaling, the signaling may also adopt the format of anincrement signaling. For example, when being transmitted by using adedicated signaling, the updated system information may include only thepart of system information related to the change, while the otherinformation that is irrelevant to the change is excluded. For anotherexample, the second dedicated signaling may include only the systeminformation that is related to the component carrier to be added or tothe carrier segment and that affects the CA transmission.

FIG. 37 is a schematic diagram showing the process of obtaining theupdated system information by the user equipment when a componentcarrier is added under carrier aggregation scenario (i.e. obtaining thesystem information related to the component carrier to be added). Asshown in FIG. 37, it is supposed that the cell corresponding to thecomponent carrier CC1 of the user equipment UE is the first cell (thespecial cell) of the user equipment and that a component carrier CC2 isto be added for the user equipment. Firstly, the user equipmentestablishes an RRC (Radio Resource Control) connection with CC1 (thespecial cell) (the RRC connection can be established by using anyappropriate method, the description of which is omitted). The systeminformation of the component carrier CC2 to be added may be carried byusing the extension of the RRCConnectionReconfiguration message. Theuser equipment may obtain the message via the cell corresponding to CC1.Then the user equipment may activate the component carrier CC2 by usingthe system information contained in the message. By using this method,the CA transmission may be facilitated.

Extension Carrier

An extension carrier is a carrier that can not be used independently; itbelongs to a set of component carriers which includes at least onecarrier that can be used independently. The extension carrier has toco-exist with a carrier that can be used independently. Generally theextension carrier is not used to transfer the system information. Whenan extension carrier is to be added to a currently used componentcarrier, the related system information may be transferred by using thetransmitting and receiving methods as shown in FIG. 27 and FIG. 28.

Further, the channel configuration of the extension carrier may bedifferent from that of other types of carriers. For example, anextension carrier does not contain RACH, PDCCH, and PUCCH channels, andthe like. Thus, when transmitting the system information in SIB2, suchinformation can be omitted. In this way, the amount of transmittedinformation can be further reduced.

By using the method as shown in FIG. 27 and FIG. 28 to transmit andreceive the system information related to the extension carrier by usingthe dedicated signaling of the first cell, the overhead for listening tothe broadcast channel can be avoided.

As described above, the change of the system information may include thecase of adding an extension carrier. In other words, the methods shownin FIGS. 2-26 and the apparatuses and systems shown in FIGS. 31-36 to bedescribed below may also be applied to transmit and receive the systeminformation related to the extension carrier, the description of whichis not repeated here.

Carrier Segment

A carrier segment can be considered as a backward compatible datatransmission extension on component carrier, in which some consecutiveresources blocks are attached to a backward compatible component carrierso that the resulted component carrier can be used a backwardincompatible component carrier to be sued by the LTE-A user equipment.

The methods of providing and receiving the system information shown inFIGS. 27-28 may be applied to the case that the component carrier to beadded contains a carrier segment.

The methods of providing and receiving the system information and themethods of updating the system information shown in FIG. 2 to FIG. 26each can be applied to the case of attaching a carrier segment to acurrently used (activated) component carrier. As an example, in suchcase, the first information/the notification information may includeinformation indicating the carrier segment to be added. As anotherexample, the carrier segment to be added to the currently used componentcarrier may be expressed by an indicator (also referred to the thirdindicator, e.g. CarrierSegmentIndicator). If a CA-NS user equipmentreceives the information transmitted from the base station, it may judgewhether to accept the system information based on the third indicator.If the third indicator indicates that a carrier segment is to be added,the CA-NS user equipment will not accept the system information. Thatis, the scenario of adding a carrier segment will not affects the CA-NSuser equipments.

In an example, if the method shown in FIG. 11, FIG. 13, or FIG. 15 isused to add a carrier segment to a currently used component carrier(i.e. transmitting the first information/the notification informationvia the first cell by using a dedicated signaling and transmittingconfiguration information related to the carrier segment via thebroadcast channel of the corresponding cell, i.e. the cell correspondingto the component carrier to which the carrier segment is to be added),the base station may encapsulate the first information or thenotification information containing the third indicator in the firstdedicated signaling in which the third indicator is set as valid. In thebroadcast channel of the corresponding cell, the system informationrelated to the carrier segment is broadcast via the second broadcastsignaling. However, no update notification is added in the secondbroadcast signaling, so as to be compatible with LTE Release 8. For auser equipment which does not support LTE-A, the change of the systeminformation is transparent. That is, if a user equipment does notsupport LTE-A, it will not receive the first dedicated signaling andwill not listen to the broadcast channel of the corresponding cell onwhich the updated system information is transferred. After a userequipment supporting LTE-A receives the first information ornotification information and determines that the third indicator isvalid, it begins to listen to the broadcast channel of thecorresponding, to receive the updated system information.

In another example, if the method shown in FIG. 12, FIG. 14, or FIG. 15is used to add a carrier segment to a currently used component carrier(i.e. transmitting the first information/the notification informationvia the broadcast channel of the first cell and transmittingconfiguration information related to the carrier segment via thebroadcast channel of the corresponding cell, i.e. the cell correspondingto the component carrier to which the carrier segment is to be added),the base station may encapsulate the first information or thenotification information containing the third indicator in the firstbroadcast signaling in which the third indicator is set as valid. In thebroadcast channel of the corresponding cell, the updated systeminformation, i.e. the system information related to the carrier segment,is broadcast via the second broadcast signaling. If a user equipmentdoes not support LTE-A, it will not listen to the broadcast channel ofthe corresponding cell on which the updated system information istransferred (or ignore the broadcast updated system information) afterit receives the first information or the notification information anddetermines that the third indicator is valid. After a user equipmentsupporting LTE-A receives the first information or notificationinformation and determines that the third indicator is valid, it beginsto listen to the broadcast channel of the corresponding, to receive theupdated system information

FIG. 29 shows a method of providing the system information related to acarrier segment in the case that the carrier segment is to be attachedto a currently used component carrier according to another embodiment ofthe disclosure. In the method of FIG. 29, the related system informationis transmitted to the user equipment directly via the cell correspondingto the currently used component carrier.

As shown in FIG. 29, in step S2902, when adding a carrier segment to thecurrently used component carrier, the system information related to thecarrier segment is generated, and the information indicating that acarrier segment is to be added may also be generated. Particularly, thesystem information may be obtained from corresponding configuration fileby the base station of the communication system. In step S2904, thegenerated information is sent via the cell corresponding to thecurrently used component carrier. As an example, the system informationcan be encapsulated in a dedicated signaling (also called as the fourthdedicated signaling), and the fourth dedicated signaling is transmittedvia the dedicated channel of the cell. As another example, the systeminformation can be encapsulated in a broadcast signaling (also called asthe third broadcast signaling), and the third broadcast signaling istransmitted via the broadcast channel of the cell.

FIG. 30 shows a method of receiving the system information related tothe carrier segment when adding the carrier segment to the currentlyused component carrier, which corresponds to the transmitting processshown FIG. 29. As shown in FIG. 30, in step S3003 the user equipmentreceives the system information related to the carrier segment and theinformation indicating that the carrier segment is to be added via thecell corresponding to the currently used component carrier. In stepS3005, the user equipment configures the carrier segment based on thesystem information, to activate the carrier segment. In the case thatthe system information is encapsulated in the fourth dedicatedsignaling, the user equipment receives the fourth dedicated signalingvia the dedicated channel of the cell, parses the fourth dedicatedsignaling to obtain the system information, and configures the carriersegment based on the system information. In the case that the systeminformation is encapsulated in the third broadcast signaling, the userequipment receives the third broadcast signaling by listening to thebroadcast channel of the cell, parses the third broadcast signaling toobtain the system information, and configures the carrier segment basedon the system information.

The transmitting method shown in FIG. 29 and the receiving method shownin FIG. 30 may also be used to add an extension carrier to a currentlyused component carrier, the description of which is not repeated here.

FIG. 31 shows an apparatus of providing the system information in theCA-S communication system according to an embodiment of the disclosure.As shown in FIG. 31, the apparatus includes: an information generateddevice 3102, a cell determining device 3104 and a transmitting device3106.

The information generated device 3102 may generate the first informationwhen the system information of the communication system changes. Thefirst information contains information that the system informationchanges. The related information can be obtained from the correspondingconfiguration file in the base station of the communication system, todetermine whether the system information changes or not.

The cell determining device 3104 may determines the first cell of a userequipment involved in the change of the system information. The firstcell is one of the cells to which the user equipment is connected, andcorresponds to a component carrier which is being used by the userequipment and is kept in connection with the base station of thecommunication system. The first cell (the special cell) is the same asdescribed above, the description of which is not repeated here. The celldetermining device 3104 may determine the special cell of the userequipment by using the above method, the description of which is notrepeated here.

The transmitting device 3106 may transmit the first information to theuser equipment via the first cell.

The above apparatus may be configured at the network side of thecommunication system, for example may be configured in the base stationof the communication system. In the CA-S communication system, the firstcell always keeps in connection with the main node (e.g. the basestation) of the communication system. Thus, by using the aboveapparatus, the case that the user equipment can not receive the updatedsystem information can be avoided, so that the system information can beupdated or provided in time. In addition, the base station needs not totransmit the system information or notify the update of the systeminformation via each of the cells supported by the user equipment,thereby decreasing the signaling load of the whole system.

In an example, the information generated device 3102 may be furtherconfigured to encapsulate the first information in a dedicated signaling(the first dedicated signaling), and the transmitting device 3106 maytransmit the first dedicated signaling to the user equipment via thefirst cell, i.e. via the dedicated channel of the first cell.

In another example, the information generated device 3102 may be furtherconfigured to encapsulate the first information in a broadcast signaling(the first broadcast signaling) and the transmitting device 3106 maytransmit the first broadcast signaling to the user equipment via thebroadcast channel of the first cell.

FIG. 32 shows an apparatus of receiving the system information in theCA-S communication system according to an embodiment of the disclosure.As shown in FIG. 32, the apparatus includes: a receiving device 3203 anda control device 3205.

The receiving device 3203 may receive the first information containingthe information indicating that the system information changes via thefirst cell.

The control device 3205 parses the first information to obtain theinformation indicating that the system information changes.

The apparatus of receiving the system information may be configured inthe user equipment of the communication system. With apparatus ofreceiving the system information, the user equipment can know the changeof the system information in time. Since the first cell (the specialcell) is always connected to the base station, the case that theinformation can not be received is avoided. In addition, the userequipment needs not to listen to all the cells corresponding to all ofits supportable component carriers, by which the power consumption ofthe user equipment can be reduced significantly and the life time of thebattery of the user equipment can be lengthened.

In the case that the first information is encapsulated in the firstdedicated signaling, the receiving device 3203 may be configured to:receive the first dedicated signaling containing the first informationvia the first cell, i.e. via the dedicated channel of the first cell.

In the case that the first information is encapsulated in the firstbroadcast signaling, the receiving device 3203 may receive the firstbroadcast signaling containing the first information via the broadcastchannel of the first cell, e.g. by listening to the broadcast channel ofthe first cell.

According to an embodiment, a CA-S communication system may include theabove apparatus of providing the system information and the apparatus ofreceiving the system information, for transferring and updating thesystem information.

Similar to the methods shown in FIG. 2 to FIG. 8, the first informationmay include only the information indicating that the system informationchanges (also called as the notification information). The apparatusesof transmitting and receiving the same are described below withreference to FIG. 33 and FIG. 34.

As another embodiment, the first information generated by theinformation generated device 3102 may also include the updated systeminformation, and the transmitting device 3106 may transmit the firstinformation containing the updated system information to the userequipment via the first cell (e.g. by the first broadcast signaling orthe first dedicated signaling). And at the side of the user equipment,the control device 3205 parses the first information to obtain theupdated system information. As an example, the first information mayalso include the information indicating whether the change of the systeminformation affects the CA transmission (also called as the thirdinformation). For example, the third information may indicate the systeminformation of which part(s) of the communication system changes and theuser equipment (the control device) may determine whether the CAtransmission is affected by this information.

As another embodiment, the change of the system information may includethe case of adding a carrier segment and/or an extension carrier to acurrently used component carrier. In this case, the first informationmay include the system information related to the carrier segment and/orthe extension carrier. When the receiving device 3203 receives the firstinformation via the first cell (e.g. by the first broadcast signaling orthe first dedicated signaling), the control device 3205 parses the firstinformation to know that the carrier segment and/or the extensioncarrier is to be added and to obtain the system information related tothe carrier segment and/or the extension carrier, and then configure thecarrier segment and/or the extension carrier based on the systeminformation.

FIG. 33 shows an apparatus of notifying update of the system informationin a CA-S communication system according to an embodiment of thedisclosure. As shown in FIG. 33, the apparatus includes: a notificationgenerating device 3302, a cell determining device 3304 and atransmitting device 3306.

The notification generating device 3302 may generate the notificationinformation indicating that the system information changes when thesystem information of the communication system changes. The notificationinformation is an example of the first information.

The cell determining device 3304 determines the first cell of a userequipment involved in the change of the system information. The firstcell is one of the cells to which the user equipment is connected, andcorresponds to a component carrier which is being used by the userequipment and is kept in connection with the base station of thecommunication system. The first cell (the special cell) is the same asdescribed above, the description of which is not repeated here. The celldetermining device 3104 may determine the special cell of the userequipment by using the above method, the description of which is notrepeated here. The cell determining device 3304 may determine thespecial cell of the user equipment by using any of the above describedmethod, the description of which is not repeated here.

The transmitting device 3306 may transmit to the user equipment thenotification information via the first cell.

In an example, the notification generating device 3302 may encapsulatethe notification information in a dedicated signaling (the firstdedicated signaling), and the transmitting device 3306 transmits thefirst dedicated signaling to the user equipment via the first cell, viathe dedicated channel of the first cell. In another example, thenotification generating device 3302 may encapsulate the notificationinformation in a broadcast signaling (the first broadcast signaling),and the transmitting device 3306 transmits the first broadcast signalingto the user equipment via the broadcast channel of the first cell.

FIG. 34 shows an apparatus of receiving the notification of update ofthe system information in a CA-S communication system according to anembodiment of the disclosure. As shown in FIG. 34, the apparatusincludes: a notification receiving device 340 and a control device 3405.

The notification receiving device 3403 receives via the first cell thenotification information transmitted from the network side of thecommunication system (the base station). The notification informationcontains information indicating that the system information changes.

The control device 3405 parses the notification information to get awarethat the system information of the communication system changes.

The apparatus of receiving the notification may be configured in theuser equipment of the communication system. With the apparatus, the userequipment can get the notification of the change of the systeminformation in time. Since the first cell (the special cell) is alwaysconnected to the base station, the case that the information can not bereceived is avoided. In addition, the user equipment needs not to listento all the cells corresponding to all of its supportable componentcarriers, by which the power consumption of the user equipment can bereduced significantly and the life time of the battery of the userequipment can be lengthened.

If the notification information is encapsulated in the first dedicatedsignaling, the receiving device 3403 may be configured to: receive thefirst dedicated signaling containing the notification information viathe first cell, i.e. via the dedicated channel of the first cell.

In the case that the notification information is encapsulated in thefirst broadcast signaling, the receiving device 3403 may receive thefirst broadcast signaling containing the notification information viathe broadcast channel of the first cell, e.g. by listening to thebroadcast channel of the first cell.

In an example, the notification generating device 3302 may encapsulatethe updated system information in a broadcast signaling (the secondbroadcast signaling), and the transmitting device 3306 may transmit thesecond broadcast signaling to the user equipment via the broadcastchannel of the cell (the second cell) corresponding to the componentcarrier involved in the change of the system information. In this case,at the side of the user equipment, the control device 3405 parses thenotification information to know the change of the system information,and indicates the receiving device 3403 to listen to the broadcastchannels of all the cells corresponding to all of the component carrierssupported by the user equipment, to receive the updated systeminformation transmitted from the network side (the base station) of thecommunication system.

As another example, the notification information generated by thenotification generating device 3302 may further include the informationfor identifying a component carrier involved in the change of the systeminformation (the second information). When the receiving device 3403 ofthe user equipment receives the notification information containing thesecond information, the control device 3405 parses the notificationinformation to obtain the second information to know the componentcarrier involved in the change of the system information based on thesecond information, and then instructs the receiving device 3403 tolisten to the broadcast channel of the cell corresponding to thiscomponent carrier to receive the updated system is information. Thus theuser equipment needs not to listen to all the cells, by which the powerconsumption of the user equipment can be reduced and the life time ofthe battery of the user equipment can be lengthened.

As another example, the notification information generated by thenotification generating device 3302 may further include information (thethird information) for identifying whether the change of the systeminformation affects the CA transmission. When the receiving device 3403of the user equipment receives the notification information containingthe third information, the control device 3405 parses the notificationinformation to obtain the third information, and based on the thirdinformation, decides whether to receive the updated system information.For example, if the user equipment supports CA and the third informationindicates that the change of the system information does not affect CAtransmission, the control device 3405 may choose to not receive theupdated system information, and i.e. it does not instruct the receivingdevice 3403 to receive the updated system information. If the userequipment does not support CA and the third information indicates thatthe change of the system information affects the CA transmission, theuser equipment chooses to not receive the updated system information. Ifthe control device 3405 determines that the change of the systeminformation affects the CA transmission based on the third informationand decides to receive the updated system information, it instructs thereceiving device 3403 to listen to the corresponding cell to receive theupdated system information.

As another example, the notification generating device 3302 mayencapsulate the updated system information in a dedicated signaling(also called as the third dedicated signaling) and the signaling may betransmitted and received via the dedicated channel of the second cell.In the embodiment, the notification information includes the information(the second information) for identifying the component carrier involvedin the change of the system information. When the receiving device 3403of the user equipment receives the notification information containingthe second information, the control device 3405 parses the notificationinformation to obtain the second information, and based on the secondinformation, instructs the receiving device 3403 to listen to thededicated channel of the cell corresponding to this component carrier,so as to receive the updated system information. In the embodiment, theuser equipment needs not to listen to other cells corresponding to theother component carriers supported by it, by which the power consumptionof the user equipment can be reduced and the life time of the battery ofthe user equipment can be lengthened.

Similar to the above method embodiments, the broadcast signaling and/orthe dedicated signaling may be newly defined signaling, or may beextension to known signaling, the description of which are omittedherein.

According to an embodiment, a CA-S communication system may include theabove apparatus of notifying the update of the system information andthe apparatus of receiving the notification of the update of the systeminformation, for notifying the update of the system information.

FIG. 35 shows an apparatus of transmitting the system information whenadding a component carrier according to an embodiment of the disclosure.As shown in FIG. 35, the apparatus includes: a dedicated signalinggenerating device 3502, a cell determining device 3504 and atransmitting device 3506.

The dedicated signaling generating device 3502 may generate the firstinformation when a component carrier is to added, the first informationincludes the information indicating that the component carrier is to beadded and the system information related to the component carrier to beadded. The dedicated signaling generating device 3502 may be configuredto encapsulate the first information in the second dedicated signaling.

The cell determining device 3504 may determine the first cell of theuser equipment involved in the change of the system information. Thefirst cell (the special cell) is the same as described above, thedescription of which is not repeated here. The cell determining device3104 may determine the special cell of the user equipment by using theabove method, the description of which is not repeated here. The celldetermining device 3304 may determine the special cell of the userequipment by using any of the above described method, the description ofwhich is not repeated here. The cell determining device 3504 maydetermine the special cell of the user equipment by using any of theabove described methods, the description of which is not repeated here.

The transmitting device 3506 transmits the second dedicated signaling tothe user equipment via the first cell, via the dedicated channel of thefirst cell.

FIG. 36 shows an apparatus of receiving the system information when acomponent carrier is to be added, which corresponds to the apparatus ofproviding the system information shown in FIG. 35. As shown in FIG. 36,the apparatus includes: a dedicated signaling receiving device 3603 anda control device 3605.

The signaling receiving device 3603 may be configured to receive thesecond dedicated signaling containing the first information whichincludes the system information related to the component carrier to beadded via the first cell. The control device 3605 is configured to parsethe second dedicated signaling to know that the component carrier is tobe added and to obtain the system information related to the componentcarrier, and then configure the component carrier based on the systeminformation related to this component carrier.

Since the system information is transmitted via the first cell by usingthe dedicated signaling, the user equipment needs not to listen to thebroadcast channels of all the cells. In addition, by using the dedicatedsignaling, such information becomes transparent to those CA-NS userequipments.

In an example, the component carrier to be added may be an extensioncarrier, and the first information generated by the dedicated signalinggenerating device 3502 may further include the system informationrelated to the extension carrier. Accordingly, when the signalingreceiving device 3603 receives the second dedicated signaling containingthe first information, the control device 3605 parses the seconddedicated signaling to know the extension carrier to be added and toobtain the system information related to the extension carrier, andconfigures the extension carrier based on the information.

In another example, the component carrier to be added may include acarrier segment to be attached to the component carrier. The dedicatedsignaling generating device 3502 is further configured to generate thesystem information related to the carrier segment, and the transmittingdevice 3506 is further configured to transmit the system informationrelated to the carrier segment to the user equipment via the first cell.For example, the system information related to the carrier segment maybe capsulated in the second dedicated signaling. Accordingly, when thesignaling receiving device 3603 receives the second dedicated signalingcontaining the first information, the control device 3605 parses thesignaling to obtain the first information to know the carrier segment isto be added and to obtain the system information related to the carriersegment, and configures the carrier segment based on the information.

According to an embodiment, a CA-S communication system may include theabove apparatuses of providing and receiving the system information, totransmit the system information in the case a component carrier isadded.

The system information and the second dedicated signaling may havesimilar formats and transmission manners as described above withreference to FIG. 27 and FIG. 28, the description of which is notrepeated here.

In some embodiments or examples, dedicated signaling is used duringtransmission of the system information, and only important systeminformation (e.g. the updated system information or importantinformation related to carrier aggregation, or the like) is transmitted,by which the starting of the CA transmission is accelerated.

In some embodiments or examples, during transmission of the systeminformation, system information update notification message istransmitted by using a cell (e.g. the special cell) corresponding to acertain component carrier, by which the receipt accuracy of the systemupdate notification message is improved, the energy consumption of theuser equipment and monitoring load is lowered, and the life time of thebattery of the user equipment is lengthened.

It should be understood that the above embodiments and examples areillustrative, rather than exhaustive. The present disclosure should notbe regarded as being limited to any particular embodiments or examplesstated above.

In the above embodiments and examples, the expressions, such as “thefirst”, “the second”, and “the third” (e.g. the first dedicatedsignaling, and the second dedicated signaling, and the like), are used.Those skilled in the art will appreciate that such expressions are usedmerely to differentiate the terms in literal, and should not beconsidered as defining the sequence or the like of the terms.

As an example, the components, units or steps in the above apparatusesand methods can be configured with software, hardware, firmware or anycombination thereof in the main node (e.g. the base station) of thecommunication network, as part of the radio resource control apparatusof the base station. The components, units or steps in the aboveresource allocating apparatuses and methods can be configured withsoftware, hardware, firmware or any combination thereof by using anyappropriate means or manners known in the art, the description of whichis not detailed herein.

As an example, the above apparatuses and methods can be realized in anexisting radio resource control apparatus of the base station bymodifying the components of the existing radio resource controlapparatus.

As an example, in the case of using software or firmware, programsconstituting the software for realizing the above method or apparatuscan be installed to a computer with a specialized hardware structure(e.g. the general purposed computer 3800 as shown in FIG. 38) from astorage medium or a network. The computer, when installed with variousprograms, is capable of carrying out various functions.

In FIG. 38, a central processing unit (CPU) 3801 executes various typesof processing in accordance with programs stored in a read-only memory(ROM) 3802, or programs loaded from a storage unit 3808 into a randomaccess memory (RAM) 3803. The RAM 3803 also stores the data required forthe CPU 3801 to execute various types of processing, as required. TheCPU 3801, the ROM 3802, and the RAM 3803 are connected to one anotherthrough a bus 3804. The bus 3804 is also connected to an input/outputinterface 3805.

The input/output interface 3805 is connected to an input unit 3806composed of a keyboard, a mouse, etc., an output unit 3807 composed of acathode ray tube or a liquid crystal display, a speaker, etc., thestorage unit 3808, which includes a hard disk, and a communication unit3809 composed of a modem, a terminal adapter, etc. The communicationunit 3809 performs communicating processing. A drive 3810 is connectedto the input/output interface 3805, if needed. In the drive 3810, forexample, removable media 3811 is loaded as a recording medium containinga program of the present invention. The program is read from theremovable media 3811 and is installed into the storage unit 3808, asrequired.

In the case of using software to realize the above consecutiveprocessing, the programs constituting the software may be installed froma network such as Internet or a storage medium such as the removablemedia 3811.

Those skilled in the art should understand the storage medium is notlimited to the removable media 3811, such as, a magnetic disk (includingflexible disc), an optical disc (including compact-disc ROM (CD-ROM) anddigital versatile disk (DVD)), an magneto-optical disc (including an MD(Mini-Disc) (registered trademark)), or a semiconductor memory, in whichthe program is recorded and which are distributed to deliver the programto the user aside from a main body of a device, or the ROM 3802 or thehard disc involved in the storage unit 3808, where the program isrecorded and which are previously mounted on the main body of the deviceand delivered to the user.

The present disclosure further provides a program product havingmachine-readable instruction codes which, when being executed, may carryout the methods according to the embodiments.

Accordingly, the storage medium for bearing the program product havingthe machine-readable instruction codes is also included in thedisclosure. The storage medium includes but not limited to a flexibledisk, an optical disc, a magneto-optical disc, a storage card, or amemory stick, or the like.

In the above description of the embodiments, features described or shownwith respect to one embodiment may be used in one or more otherembodiments in a similar or same manner, or may be combined with thefeatures of the other embodiments, or may be used to replace thefeatures of the other embodiments.

As used herein, the terms the terms “comprise,” “include,” “have” andany variations thereof, are intended to cover a non-exclusive inclusion,such that a process, method, article, or apparatus that comprises a listof elements is not necessarily limited to those elements, but mayinclude other elements not expressly listed or inherent to such process,method, article, or apparatus.

Further, in the disclosure the methods are not limited to a processperformed in temporal sequence according to the order described therein,instead, they can be executed in other temporal sequence, or be executedin parallel or separatively. For example, in some embodiments the stepof determining the first cell may be performed before the step ofgenerating the first information or the notification information. Thatis, the executing orders described above should not be regarded aslimiting the method thereto.

While some embodiments and examples have been disclosed above, it shouldbe noted that these embodiments and examples are only used to illustratethe present disclosure but not to limit the present disclosure. Variousmodifications, improvements and equivalents can be made by those skilledin the art without departing from the scope of the present disclosure.Such modifications, improvements and equivalents should also be regardedas being covered by the protection scope of the present disclosure.

The invention claimed is:
 1. A method of providing system information in a communication system supporting carrier aggregation, comprising: generating, when there is a change in system information of the communication system, first information which comprises information indicating that there is a change in system information; determining a first cell of a user equipment involved in the change in system information, wherein the first cell is one of cells to which the user equipment is connected and corresponds to a component carrier which is being used by the user equipment and is kept in connection with a base station of the communication system; and transmitting the first information to the user equipment via the first cell, wherein the change in system information comprises adding a component carrier for the user equipment, the first information further comprises system information associated with the component carrier to be added, and transmitting the first information to the user equipment via the first cell comprises encapsulating the first information in a second dedicated signaling and transmitting the second dedicated signaling to the user equipment via the first cell, the first information further comprises system information comprising configuration information on transmission bandwidth and information indicating frequency bands associated with the component carrier to be added, and when the component carrier to be added is for downlink transmission, the system information further comprises configuration information for downlink channels of the component carrier to be added.
 2. The method according to claim 1, wherein transmitting the first information to the user equipment via the first cell comprises: encapsulating the first information in a first broadcast signaling; and transmitting the first broadcast signaling to the user equipment via a broadcast channel of the first cell.
 3. The method according to claim 2, further comprising: encapsulating updated system information in a second broadcast signaling; and transmitting the second broadcast signaling to the user equipment via a broadcast channel of a second cell corresponding to a component carrier involved in the change in system information.
 4. The method according to claim 3, wherein the first information further comprises second information identifying the component carrier involved in the change in system information.
 5. The method according to claim 1, wherein the first information further comprises third information indicating whether the change in system information affects carrier aggregation transmission.
 6. The method according to claim 1, wherein when the change in system information comprises attaching a carrier segment to a component carrier involved in the change, the first information further comprises configuration information associated with the carrier segment.
 7. The method according to claim 1, wherein the first information further comprises updated system information.
 8. The method according to claim 1, wherein the component carrier to be added is an extension carrier, and wherein encapsulating the first information in the second dedicated signaling comprises: encapsulating configuration information associated with the extension carrier in the second dedicated signaling.
 9. The method according to claim 1, wherein the component carrier to be added comprises a carrier segment to be attached to the component carrier to be added, and the method further comprises: transmitting configuration information associated with the carrier segment to the user equipment via the first cell.
 10. The method according to claim 1, wherein: when the component carrier to be added is for uplink transmission or when the component carrier to be added is for downlink transmission but needs uplink information to be configured, the system information further comprises uplink carrier frequency, uplink transmission bandwidth, configuration information for uplink channels of the component carrier to be added.
 11. The method according to claim 1, wherein the second dedicated signaling is an extension to an existing radio source control connection reconfiguration message, and wherein encapsulating the first information in the second dedicated signaling comprises: encapsulating the first information in the existing radio source control connection reconfiguration message.
 12. The method according to claim 1, wherein the second dedicated signaling comprises only system information that is associated with the component carrier to be added and affects carrier aggregation transmission.
 13. An apparatus of providing system information in a communication system supporting carrier aggregation, comprising: an information generating device, configured to generate, when there is a change in system information of the communication system, first information which comprises information indicating that there is a change in system information; a cell determining device, configured to determine a first cell of a user equipment involved in the change in system information, wherein the first cell is one of cells to which the user equipment is connected and corresponds to a component carrier which is being used by the user equipment and is kept in connection with a base station of the communication system; and a transmitting device, configured to transmit the first information to the user equipment via the first cell, wherein the change in system information comprises adding a component carrier for the user equipment, the first information further comprises system information associated with the component carrier to be added, and wherein the information generating device is further configured to encapsulate the first information in a second dedicated signaling; and the transmitting device is further configured to transmit the second dedicated signaling to the user equipment via the first cell, the system information comprises configuration information on transmission bandwidth and information indicating frequency bands associated with the component carrier to be added, and when the component carrier to be added is for downlink transmission, the system information further comprises configuration information for downlink channels of the component carrier to be added.
 14. The apparatus according to claim 13, wherein: the information generating device is further configured to encapsulate the first information in a first broadcast signaling; and the transmitting device is further configured to transmit the first broadcast signaling to the user equipment via a broadcast channel of the first cell.
 15. The apparatus according to claim 14, wherein: the information generating device is further configured to encapsulate updated system information in a second broadcast signaling; and the transmitting device is further configured to transmit the second broadcast signaling to the user equipment via a broadcast channel of a second cell corresponding to a component carrier involved in the change in system information.
 16. The apparatus according to claim 15, wherein the first information further comprises second information identifying the component carrier involved in the change in system information.
 17. The apparatus according to claim 13, wherein the first information further comprises third information indicating whether the change in system information affects carrier aggregation transmission.
 18. The apparatus according to claim 13, wherein when the change in system information comprises attaching a carrier segment to a component carrier involved in the change, the first information further comprises configuration information associated with the carrier segment.
 19. The apparatus according to claim 13, wherein the first information further comprises updated system information.
 20. The apparatus according to claim 13, wherein the component carrier to be added is an extension carrier, and the first information further comprises configuration information associated with the extension carrier.
 21. The apparatus according to claim 13, wherein the component carrier to be added comprises a carrier segment to be attached to the component carrier to be added, and wherein the transmitting device is further configured to transmit configuration information associated with the carrier segment to the user equipment via the first cell.
 22. The apparatus according to claim 13, wherein: when the component carrier to be added is for uplink transmission or when the component carrier to be added is for downlink transmission but needs uplink information to be configured, the system information further comprises uplink carrier frequency, uplink transmission bandwidth, configuration information for uplink channels of the component carrier to be added.
 23. The apparatus according to claim 13, wherein the second dedicated signaling is an extension to an existing radio source control connection reconfiguration message, and wherein the information generating device is configured to encapsulate the first information in the existing radio source control connection reconfiguration message.
 24. The apparatus according to claim 13, wherein the second dedicated signaling comprises only system information that is associated with the component carrier to be added and affects carrier aggregation transmission.
 25. A method of receiving system information in a communication system supporting carrier aggregation, comprising: receiving first information which comprises information indicating that there is a change in system information of the communication system via a first cell corresponding to a component carrier which is being used by a user equipment of the communication system and is kept in connection with a base station of the communication system; and parsing the first information, to obtain the information indicating that there is a change in system information, wherein the change in system information comprises adding a component carrier for the user equipment, the first information further comprises system information associated with the component carrier to be added, and wherein receiving the first information via the first cell comprises: receiving a second dedicated signaling in which the first information is encapsulated via the first cell, and parsing the first information comprises: parsing the second dedicated signaling, to obtain the system information associated with the component carrier to be added from the first information, and wherein the method further comprises: configuring the component carrier to be added based on the system information associated with the component carrier to be added, wherein the system information comprises configuration information on transmission bandwidth and information indicating frequency bands associated with the component carrier to be added, and when the component carrier to be added is for downlink transmission, the system information further comprises configuration information for downlink channels of the component carrier to be added.
 26. The method according to claim 25, wherein receiving the first information via the first cell comprises: receiving a first broadcast signaling in which the first information is encapsulated via a broadcast channel of the first cell.
 27. The method according to claim 26, wherein the first information further comprises second information identifying a component carrier involved in the change in system information, and the method further comprise: obtaining the second information identifying the component carrier involved in the change in system information from the first information; and receiving a second broadcasting signaling in which updated system information is encapsulated via a broadcast channel of a second cell corresponding to the component carrier involved.
 28. The method according to claim 26, further comprising: receiving a second broadcasting signaling in which updated system information is encapsulated by listening to a broadcast channel of each cell corresponding to each component carrier that is being used by the user equipment.
 29. The method according to claim 25, wherein the first information further comprises third information indicating whether the change in system information affects carrier aggregation transmission, and the method further comprises: judging whether to receive updated system information based on the third information.
 30. The method according to claim 25, wherein the change in system information comprises attaching a carrier segment to a component carrier involved in the change, the first information further comprises configuration information associated with the carrier segment, and wherein the method further comprises: obtaining the configuration information associated with the carrier segment from the first information; and configuring the carrier segment according to the configuration information associated with the carrier segment.
 31. The method according to claim 25, wherein the first information further comprises updated system information, and the method further comprises: obtaining the updated system information from the first information.
 32. The method according to claim 25, wherein the component carrier to be added is an extension carrier, and wherein receiving the second dedicated signaling in which the first information is encapsulated via the first cell comprises: receiving the second dedicated signaling in which configuration information associated with the extension carrier is encapsulated via the first cell.
 33. The method according to claim 25, wherein the component carrier to be added comprises a carrier segment to be attached to the component carrier to be added, and the method further comprises: receiving configuration information associated with the carrier segment via the first cell; and configuring the carrier segment based on the configuration information associated with the carrier segment.
 34. The method according to claim 25, wherein: when the component carrier to be added is for uplink transmission or when the component carrier to be added is for downlink transmission but needs uplink information to be configured, the system information further comprises uplink carrier frequency, uplink transmission bandwidth, configuration information for uplink channels of the component carrier to be added.
 35. The method according to claim 25, wherein the second dedicated signaling is an extension to an existing radio source control connection reconfiguration message.
 36. The method according to claim 25, wherein the second dedicated signaling comprises only system information that is associated with the component carrier to be added and affects carrier aggregation transmission.
 37. An apparatus of receiving system information in a communication system supporting carrier aggregation, comprising: a receiving device, configured to receive first information which comprises information indicating that there is a change in system information of the communication system via a first cell corresponding to a component carrier which is being used by the apparatus and is kept in connection with a base station of the communication system; and a control device, configured to parse the first information, to obtain the information indicating that there is a change in system information, wherein the change in system information comprises adding a component carrier for the apparatus, the first information further comprises system information associated with the component carrier to be added, and wherein the receiving device is further configured to receive a second dedicated signaling in which the first information is encapsulated via the first cell, and the control device is further configured to parse the second dedicated signaling to obtain the system information associated with the component carrier to be added from the first information, and configure the component carrier to be added according to the system information associated with the component carrier to be added, wherein the system information comprises configuration information on transmission bandwidth and information indicating frequency bands associated with the component carrier to be added, and when the component carrier to be added is for downlink transmission, the system information further comprises configuration information for downlink channels of the component carrier to be added.
 38. The apparatus according to claim 37, wherein the receiving device is further configured to receive a first broadcast signaling in which the first information is encapsulated via a broadcast channel of the first cell.
 39. The apparatus according to claim 38, wherein the first information further comprises second information identifying a component carrier involved in the change in system information, and the control device is further configured to: obtain the second information identifying the component carrier involved in the change in system information from the first information; and control the receiving device to receive a second broadcasting signaling in which updated system information is encapsulated via a broadcast channel of a second cell corresponding to the component carrier involved.
 40. The apparatus according to claim 38, wherein the receiving device is further configured to receive a second broadcasting signaling in which updated system information is encapsulated by listening to a broadcast channel of each cell corresponding to each component carrier that is being used by the user equipment.
 41. The apparatus according to claim 37, wherein the first information further comprises third information indicating whether the change in system information affects carrier aggregation transmission, and the control device is further configured to judge whether to receive updated system information based on the third information.
 42. The apparatus according to claim 37, wherein the change in system information comprises attaching a carrier segment to a component carrier involved in the change, the first information further comprises configuration information associated with the carrier segment, and wherein the control device is further configured to obtain the configuration information associated with the carrier segment from the first information, and configure the carrier segment according to the configuration information associated with the carrier segment.
 43. The apparatus according to claim 37, wherein the first information further comprises updated system information, and the control device is further configured to obtain the updated system information from the first information.
 44. The apparatus according to claim 37, wherein the component carrier to be added is an extension carrier, and wherein the receiving device is further configured to receive the second dedicated signaling in which configuration information associated with the extension carrier is encapsulated via the first cell.
 45. The apparatus according to claim 37, wherein the component carrier to be added comprises a carrier segment to be attached to the component carrier to be added, and wherein the receiving device is further configured to receive configuration information associated with the carrier segment via the first cell; and the control device is further configured to configure the carrier segment based on the configuration information associated with the carrier segment.
 46. The apparatus according to claim 37, wherein: when the component carrier to be added is for uplink transmission or when the component carrier to be added is for downlink transmission but needs uplink information to be configured, the system information further comprises uplink carrier frequency, uplink transmission bandwidth, configuration information for uplink channels of the component carrier to be added.
 47. The apparatus according to claim 37, wherein the second dedicated signaling is an extension to an existing radio source control connection reconfiguration message.
 48. The apparatus according to claim 37, wherein the second dedicated signaling comprises only system information that is associated with the component carrier to be added and affects carrier aggregation transmission.
 49. A non-transient recording medium that stores program codes which, when loaded into a memory of a computer and executed by a processor of the computer, cause the processor to perform the steps according to claim
 1. 50. A non-transient recording medium that stores program codes which, when loaded into a memory of a computer and executed by a processor of the computer, cause the processor to perform the steps according to claim
 25. 